Prosecutions of pimping and kerb crawling offences have nearly halved under the coalition Government, prompting accusations that ministers are taking a "lackadaisical" approach to tackling men's demand for prostitutes.

Last year (2012-13) 50 controlling prostitution, or pimping, offences were prosecuted while 233 offences of soliciting, or kerb crawling, reached the courts, Solicitor General Oliver Heald revealed.

The figures have nearly halved since the last year of the previous government ( 2009-10) when 98 pimping offences and 419 soliciting offences were prosecuted.

The charity Eaves, which helps vulnerable women abandon prostitution, denounced the lack of political will to get to grips with pimps and men who pay for prostitutes.

Shadow attorney general Emily Thornberry, who uncovered the figures using a parliamentary question, said a pattern was emerging in how the criminal justice system deals with violence against women.

Ms Thornberry compared the decline in prosecutions to the fall in the number of rape and domestic violence cases police refer to the Crown Prosecution Service.

Heather Harvey, research and development manager at Eaves, said police are more likely to penalise prostitutes, thereby trapping them in the industry, rather than tackle pimps and kerb crawlers.

Ms Harvey called on the Government to implement a similar scheme to the one operated by Lambeth Council and Lambeth police in south London, which targets kerb crawlers and runs publicity campaigns to challenge the demand for prostitutes.

She said: "We share the disappointment that these figures demonstrate such an evident lack of political will to challenge men's demand for women in prostitution or to seriously get to grips with the buyers, pimps and managers who benefit from so lackadaisical an approach.

"There are powers that police can use to challenge buyers and pimps but not only do they mostly not do so, worse they are more likely to penalise the women themselves. Criminalising women in prostitution is discriminatory as it merely compounds their exclusion and marginalisation, it traps them in prostitution making any possibility of moving on to an alternative life even harder.

"Giving women Asbos, as all too often happens, results in women being displaced and isolated from their normal social and support networks."

Ms Thornberry called on Home Secretary Theresa May to demand improvements.

She said: "I do not believe that there are 50 pimps in the UK so just 50 offences being prosecuted last year lets everybody down - they are just not trying.

"It is as if these issues are falling off the table as they have with rape, child abuse, domestic violence - it fits into a pattern.

"You have to have leadership from the Government on this. It chimes in with what was said yesterday at PMQs and the all-male front bench with a woman behind (Tory MP Anne McIntosh) who had just been deselected and been called a silly little girl."

She went on: "They are just not trying on prostitutes and pimps and it is so pathetic only prosecuting 50 pimping offences in the whole country.

"Everyone knows the exploitation of women is much greater than that and I think we then want the police to take the issue seriously.

"I think it is a question of leadership and you just can't have this issue falling off the table. I would expect the Home Secretary to pick it up and put it back on the table and say, 'I want to see improvements in this'."

The figures released by Mr Heald refer to the number of offences, not defendants, which were prosecuted and reached a first hearing in magistrates' courts. The Solicitor General also revealed there were 97 prosecutions for brothel keeping offences last year.

The figures were released by the Crown Prosecution Service and relate to England and Wales.